Corydalis kushiroensis is described as a new species from Hokkaido (northern Japan). A key to C. kushiroensis and two allied species, C. ochotensis, and C. raddeana, and their geographical distribution in Japan are presented.
Development and structure of seed-coat were examined in 16 species of Corydalis and two species of Dicentra (C. ophiocarpa, C. racemosa, C. balansae, C. heterocarpa, C. pallida, C. pterophora, C. speciosa, C. incisa, C. kushiroensis, C. ochotensis, C. raddeana, C. ambigua, C. capillipes, C. lineariloba, C. papilligera, C. decumbens, D. peregrina, D. spectabilis). Neither the tegmen (developed ii) nor the testa (developed oi) is multiplicative during seed development. Mature seed-coat is consistent in all the species examined in having mechanical structure in the exo- or endotesta. Differences are found in (1) which of the integumentary layers develops into the main mechanical layer (exotesta or endotesta), (2) whether a mesotesta is differentiated or not, and (3) whether the endotegmen is persistent as a layer of thick-walled cells, is persistent only partially, or is thoroughly degenerated. These seed-coat characters distinguish six groups of species (i.e., four groups in Corydalis and two in Dicentra), which represent well infrageneric taxa proposed on the other characters. Evidence from seed-coat anatomy further suggests and Dicentra spectabilis (subg. Hedycapnos) retains the primitive (endotestal) seed-coat of Fumarioideae.
The first overall study of pericarp anatomy of Coriaria is presented to discuss its evolution and relationships within a genus. All 14 species investigated (including 11 narrowly defined species) have somewhat bilaterally flattened mature fruits with five to seven (or more) longitudinal costae. They share a usually nine-(or more)-cell-layered (at intercostal region), stratified mature pericarp, which is basically constructed by an exocarp, an outer, a middle and an inner zone of mesocarp, and an endocarp. While a multi-layered endocarp is composed of circumferentially elongate fibres, a multi-layered inner zone of the mesocarp comprises longitudinally elongate fibres. Despite its uncertain systematic value, the presence of those fibres arranged crisscross is a characteristic feature of the genus. Comparisons among species indicate that Coriaria terminalis, a species of the Eastern Hemisphere, retains a basic or archaic, well-stratified pericarp structure similar to the one found in all the species investigated of the Southern and Western Hemisphere, and that four species of Asia, Coriaria nepalensis, C. sinica, C. intermedia and C. japonica, share a specialized structure (lacking the outer zone of the mesocarp) indicative of their mutual close affinity. Comparisons further suggest distinctness of Coriaria intermedia, a well as variously derived position of C. myrtifolia and C. japonica. (The other species discussed are C. arborea, C. angustissima, C. kingiana, C. microphylla, C. plumosa, C. pteridoides, C. ruscifolia and C. sarmentosa).
Seed-coat anatomy is described in genera of Uvulariaceae of the Northern Hemisphere. The seed-coat anatomy of Uvulariaceae is varied, and based on cell shape, distribution and pattern of wall-thickenings and deposits among cell layers, five groups of taxa are recognized within the family: (1) Uvularia and Disporum, (2) Streptopus (including S. ovalis). (3) Clintonia, (4) Tricyrtus, and (5) Prosartes. These five groups show little significant similarity to the seed-coat of Convallariaceae (Asparagales). Rather, some of the groups show similarities to genera of Liliaceae or Trilliaceae. Prosartes has a thin-walled seed-coat significantly different from Disporum, in which Prosartes has been conventionally included. The seedcoat anatomy of Streptopus ovalis, which has been sometimes assigned in Disporum (as Disporum ovale), coincides well with that of Streptopus, rather than with that of Disporum. In the most part, these groups of taxa correspond to clades recognized in recent studies of rbcL sequences.
The vascular pattern in the fruits of two Cape (South Africa) endemic genera of Fumarioideae (Papaveraceae), Trigonocapnos and Discocapnos, is depicted. Although the two genera differ much in fruit morphology, they uniquely share a marginal wing, pairwise fusion of the side branches of the dorsal and ventral bundles, and a funicular supply from the side branches. Trigonocapnos shows the further specialized conditions of termination of the dorsal and ventral bundles and of the formation of a pseudolocule by the folded wings. The results support a hypothesis of the monophyly of subtribe Discocapninae composed of these two genera.
The phylogeny of Corydalis was deduced from sequences of the transcribed spacers in the nuclear ribosomal DNA. A unique derivation of zygomorphic flowers and a basal position of a paraphyletic Dicentra is suggested. The section Strictae is sister group to the rest of the genus, which consists of two well supported clades: (Sophorocapnos, Thalictrifoliae, Aulacostigma and Cheilanthifoliae), and the majority of the genus, including all the tuberous groups. Duplotuber is far removed from the other tuberous sections.
Seed-coat anatomy is described in 122 species of Fumarioideae, which represent all the genera, subgenera, and most sections. Nine seed-coat types were recognized: (I) Dicentra subg. Hedycapnos, (II) Dicentra subg. Chrysocapnos, (III) Dicentra subg. Macranthos, (IV) Dicentra subg. Dicentra,(V) Corydalis p.p., (VI) rest of Corydaleae, Cysticapnos, Pseudofumaria and Ceratocapnos, (VII) Discocapnos and Sarcocapnos p. p., (VIII) Sarcocapnos p. p., Platycapnos and Trigonocapnos, and (IX) Fumariinae. Variable characters are polarized based on the comparison with Fumariaceae-Hypecooideae, Papaveraceae and Pteridophyllaceae. It is assumed that endotestal seed-coat type (I) is most primitive, that exotestal seed-coat types (II-VIII) are derived therefrom, and that the reduction of the mechanical layer, including the origin of thin seedcoat type (IX) occurred repeatedly in combination with indehiscent, hard-walled fruits. Dicentra subg. Hedycapnos (with type I) possesses a combination of primitive testal characters unique within the subfamily, suggesting it represents a sister group to the rest of the subfamily. Each of the other subgenera (with II, III or IV) is also characterized by a unique combination of seed-coat characters, which are found in the outgroups but not in the other genera. Seedcoat characters support the monophyly of Fumarioideae exclusive of Dicentra subg. Hedycapnos, of Fumarioideae exclusive of Dicentra, of Dicentra subg. Dicentra, of Corydalis p.p., and of Fumariinae.
The pericarp anatomy of Fumariaceae-Fumarioideae (Papaverales) is observed. Dehiscence zones, endocarp, and fiber clusters in the mesocarp (presence/absence, distribution and abundance) vary among taxa. Fiber layers or idioblastic sclereids characterize some genera. Pericarp anatomy supports the monophyly of Dicentra subg. Macranthos plus Chrysocapnos, Ceratocapnos s.l., Ceratocapnos/Sarcocapnos, Discocapininae, and Fumariinae, and suggests paraphyly of the tribe Corydaleae, and specifically of Dicentra, and similarity between Dactylicapnos, Capnoides and Corydalis. Pericarp anatomy is equivocal on other issues, e.g., the relationship of Corydaleae, Fumarieae and Cysticapnos, and the position of Platycapnos and Pseudofumaria. Combined with rDNA and seed-coat evidence, pericarp anatomy supports three major clades within Corydalis.
The phylogeny of Fumariaceae, as inferred from rps16 intron sequences, is compared with morphological data, and nrDNA-ITS. The different data sets are largely congruent and indicate that (1) Dicentra and the tribe Corydaleae as hitherto circumscribed are polyphyletic, (2) Lamprocapnos (= Dicentra spectabilis) is sister group to the rest of subfam. Fumarioideae, (3) Ehrendorferia, gen. nov. (= Dicentra chrysantha and D. ochroleuca) is basal in the latter group, (4) the morphologically aberrant Ichtyoselmis, gen. nov. (= Dicentra macrantha) groups with Dicentra s. str., (5) the genus Cysticapnos should be included in the tribe Fumarieae, (6) Dactylicapnos (= Dicentra subg. Dactylicapnos) is sister group to Corydalis, (7) the genus Corydalis is monophyletic, and consists of three subgenera: Chremnocapnos, stat. nov., Sophorocapnos, stat. nov., and Corydalis. The following new combinations are validated: Ehrendorferia chrysantha, E. ochroleuca, Ichtyoselmis macrantha, and Lamprocapnos spectabilis.
This article reports the seed and funicle morphology of Fumarioideae with dehiscent fruits, covering 11 genera (106 species) for seeds and 11 genera (48 species) for funicles. The results are discussed referring to a hypothetical phylogeny based on chloroplast DNA sequences and morphology. Weak seed curvature is a synapomorphy of the Ichtyoselmis-Dicentra clade, and the truncate hilar region and laterally elongated arilbase ambiguously support the Dactylicapnos-Corydalis clade, but in both cases, it is necessary to assume reversals or parallel changes elsewhere in the subfamily. Otherwise, seed morphological characters are poor phylogenetic markers at the genus level as a result of high homoplasy and polymorphism within the operational taxonomic units. Although seed morphology is not very informative for the phylogeny among the terminal taxa, most of them can be identified by a combination of characters. Ehrendorferia, Dicentra, Dactylicapnos sect. Dactylicapnos (except for Dactylicapnos paucinervia), Cysticapnos s. str., and Pseudofumaria each possesses a unique hilar region topography and is supported as monophyletic. Three or five independent origins of arils are assumed in Fumarioideae. This is compatible with the diversity in the location of the arils (raphe vs. raphehilar region) and with the morphology of the primordia. Each taxon possesses either hilar concavity or funicle receptacles, both of which may contribute to stabilization of seeds in fruits. The former state is assumed to have originated independently in four clades. A functional association is indicated among distinctly truncate hilar regions, platelike funicle apices, and explosive fruit dehiscence in Corydalis subg. Corydalis. These results emphasize the importance of funicle morphology in the functional interpretation of seed morphology.
Androdioecy, coexistence of hermaphrodites and males, is an extremely rare breeding system in angiosperms. In the present study, Schizopepon bryoniaefolius (Cucurbitaceae) was confirmed to be functionally androdioecious based on observations of floral and pollen morphology and bagging experiments. Six out of the 11 studied populations consisted of only hermaphrodites, while the other five populations were androdioecious and the frequencies of males were consistently lower than those of hermaphrodites (5.5-28.3%). To understand the consequences of an androdioecious breeding system, genetic variation was estimated using four polymorphic allozyme loci. The degree of genetic differentiation among 11 populations was high (GST = 0.688). Inbreeding coefficients (FIS) for all loci significantly deviated from zero. In particular, the FIS values averaged across the polymorphic loci in hermaphrodite populations were close to unity, suggesting that hermaphrodites are predominantly selfing in the absence of males. A significant negative correlation was found between the frequencies of males and inbreeding coefficients, indicating that outcrossing rates depend on the population sex ratio.
Floral characters of an annual androdioecious vine Schizopepon bryoniaefolius (Cucurbitaceae-Cucurbitoideae-Schizopeponeae) are described with special reference to the arrangement of stamens and ovary locules, vasculature, nectaries, trichomes and phenology. Both hermaphrodite and male flowers bear two dithecal and one monothecal stamens, as in many taxa of Cucurbitoideae. However, S. bryoniaefolius differs from them in that each stamen is recognized as a single mound in an early stage of the development and receives a single vascular bundle. The anther trichomes are snowman-like and are different in cell shape from those of the other previously examined taxa. There is no or small time-lag between anther dehiscence and stigma maturation in hermaphrodite flowers. In both of the sexual morphs, there is a nectary at the bottom of the receptacular cup.
The size and number of pollen grains and ovules are compared between 20 populations of different ploidy levels in two self-incompatible species of Corydalis (Fumariaceae), to test the presence of ploidy-related variation in these reproductive characters. In both species, higher ploidy levels are associated with larger pollen grains, ovules and corolla, but the number of pollen grains and ovules are not different between ploidy levels. The investment per flower is consequently larger at higher ploidy levels, but the flower number per individual is lower, suggesting that the mode of partition of the investment for sexual reproduction varies between different ploidy levels. In C. orthoceras, sex allocation estimated by pollen:ovule ratios in number and volume is more female-biased in polyploids than in diploids. In spite of these variations, the characters studied can not be used as indicators of ploidy level due to the large overlaps between the ploidy levels.
Key words: Corydalis, Fumariaceae, ovule number, ovule size, pollen number, pollen grain diameter, pollen-ovule ratio, polyploidy.
Oginuma, K., Horiuchi, K. & Fukuhara, T. 2001 Karyomorphology of two genera in Stemonaceae. Acta Phytotaxonomica et Geobotanica 52: 57-64
Chromosome numbers were reported in five species of Stemonaceae, i.e., Croomia heterosepara (2n=24), C. japonica (2n=24), Stemona japonica (2n=14), S. sessilifolia (2n=14) and S. tuberosa (2n=14). Karyotypes were also described in these species exclusive of S. tuberosa. In the classification of the centromeric position, C. heterosepara and C. japonica are identical to each other, but S. japonica and S. sessilifolia are slightly different. The present and earlier reports confirm that the three genera of Stemonaceae (s.str.) have different base number: x=12 in Croomia, x=7 in Stemona, and x=9 in Stichoneuron. With currently available phylogenetic hypotheses, the primitive base number of the family seems to be x=7.
Fukuhara, T., Nagamasu, H. & Okada, H. 2003 Floral vasculature, sporogenesis and gametophyte development in Pentastemona egregia (Stemonaceae). Systematics and Geography of Plants 73: 83-90
Floral vasculature, sporogenesis and gametophyte development are observed in Pentastemona egregia (Stemonaceae). Sporogenesis and gametophyte development agree with those of the rest of the family, but they neither provide informative evidence for the further relationship of the genus nor the affinity of the family. Floral architecture indicates that the pentamerous-monocyclic flower of Pentastemona could have been derived from trimerous-dicyclic flowers by a simple modification.